How to Disable Mailman in cPanel

Access your WHM log-in page by typing the IP number of your server followed by a colon and the number '2083' -- for example, 100.100.100.100:2083 -- in your browser window.
Enter your root server access username and password in their respective fields as soon as the cPanel WHM login screen appears. Click on the 'Login' button below the password field.
Click the 'Server Configuration' icon on your main WHM screen and then the 'Tweak settings' icon in the screen that appears afterward, or click 'Tweak settings' under 'Server configuration' at the top of your left sidebar menu.
Scroll down on the 'Tweak settings' screen list to the 'Mail' section, and continue to scroll down toward the bottom of the 'Mail' section to find 'Enable Mailman mailing lists.'
Click on the 'Off' radio button at the far right of the 'Enable Mailman mailing lists' entry line.
Scroll down to the bottom of the 'Tweak settings' menu list and click 'Save.' Wait for the list of processes to stop and the word 'Done' to appear at the bottom of the list; scroll down as necessary to find the 'Done' notification. This process takes less than a minute with a fast server and broadband Internet connection.
Click 'Home' to return to your main WHM menu or exit the WHM as you wish.
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